Mississippi HVAC Contractor Exam Guide 2026

Mississippi HVAC Exam: Step-by-Step Study Guide

Preparing for the Mississippi HVAC exam is easier one step at a time. This guide starts with the key facts from the official bulletin, then covers the topics on the exam, the reference books, sample questions with answers, and a simple way to prepare. PSI gives the exam.

Mississippi HVAC Exam Overview

Start with the facts. Here's what the official bulletin says:


Questions	80 questions
Time limit	4 hours
Passing score	70% correct
Books in the exam room	Open book
Exam fee	The examination fee is $120 for one examination portion and $240 for two examination portions, charged for each registration whether it is a first attempt or a retake.

On exam day

You must bring one valid, unexpired identification bearing your signature and photograph whose name matches your registration.
Arrive at the examination site at least 30 minutes before your appointment.
Candidates bring their own approved references, which may not be written in and may not contain any additional loose or attached papers.
Highlighting, underlining and indexing done before the exam are allowed, writing in the book is not, and only permanent tabs may be used.
A silent, battery-operated, nonprinting, non-programmable calculator without an alphabet keyboard may be used.
Personal items, including electronic devices, reading material and writing devices, must be left in secure storage outside the examination room.

References you may bring

Modern Refrigeration and Air Conditioning, Althouse, Turnquist, Bracciano (20th, 21st, or 22nd edition (Starting 8/1/2026 the 20th and 21st editions will no longer be used))
Code of Federal Regulations - 29 CFR Part 1926 (OSHA), with latest available amendments
Code of Federal Regulations - 29 CFR Part 1926 Selections by PSI, with latest available amendments
International Fuel Gas Code (2021)
HVAC Duct Construction Standards, Metal and Flexible (2005, 3rd edition)
Manual N - Load Calculation for Small Commercial Buildings (Fifth Edition, 2008)
International Mechanical Code (2021)
NFPA 58 Liquefied Petroleum Gas Code (2020 Edition, 2001)
ACCA Ductulator
Manual D (2016, 3rd Ed)
Pipefitters Handbook (3rd Edition, 1967)
Manual J - Residential Load Calcs (reprinted 2016, Eighth Full Edition)

Scheduling, changes and retakes

You schedule your examination online at https://test-takers.psiexams.com/mscontlb or by calling PSI at (855) 557-0619.
The Board must find you eligible and notify PSI before you test, and eligibility lasts 6 months from the date of eligibility.
Fees are never refunded, but you may cancel and reschedule without forfeiting your fee if PSI receives notice 2 days before the exam date, and unused funds are held for one year from the initial registration date.
Missing the appointment, arriving after the start time, cancelling late, or not presenting proper ID forfeits your registration and fee, and you must re-register.
Results are given immediately on screen, with a performance summary for passers and a diagnostic report of strengths and weaknesses for those who fail.
You may retest an unlimited number of times during your 6-month eligibility period, paying the fee each time.
After passing and meeting all licensing requirements, the Board reviews complete applications weekly and successful candidates receive their Certificate of Responsibility or Residential License about one week after Board approval.

Source: State of Mississippi Contractor Examinations Candidate Information Bulletin, Updated 4/23/2026. Check the bulletin before test day: fees and rules can change.

Topics on the Mississippi HVAC Exam

Next, the content. The official content outline has 20 topics:

Topic	Questions	Share of the exam
Piping	4	5%
Insulation	1	1%
Hangers and Supports	3	4%
Sound, Vibration and Seismic Control	1	1%
Heating and Cooling Principles	3	4%
Refrigerants and Refrigeration	6	8%
Load Calculations	10	12%
Testing, Adjusting and Balancing	1	1%
Controls	3	4%
A/C and Heat Pump Equipment	4	5%
Furnaces and Heaters	4	5%
Chimneys, Flues and Vents	3	4%
Combustion Air	2	2%
Fuel Gas Systems	9	11%
LP Gas Systems	5	6%
Ducts	10	12%
Boilers and Hydronics	4	5%
Machine Room	1	1%
Evaporative Cooling	2	2%
Safety	4	5%

A Simple Plan to Prepare for the Mississippi HVAC Exam

Step one is the books. This is an open-book exam, so the references on the bulletin's list are what you'll work from, while you study and in the exam room. Get the editions the bulletin names.

Step two is learning your way around them. Go through each book's table of contents and index until you know where the major subjects are. You don't need to memorize the books. You need to find things in them.

Step three is marking them up. Highlight the sections you use most. The exam facts above list the bulletin's rules on tabs and markings, so follow them exactly.

Step four is timed practice. Our practice exams run on a clock, so you get used to the real exam's pace: about 3 minutes per question.

Along the way, give the most time to the biggest topics. Load Calculations and Ducts make up 25% of the exam.

The last step is consistency. Keep practicing until you pass several practice exams in a row. That's the signal you're ready.

Reference Books for the Mississippi HVAC Exam

The HVAC reference list names the materials allowed in the examination center, beginning with Modern Refrigeration and Air Conditioning.

Where to get them:

On Test Day

Go through the exam at a steady pace. On your first pass, answer the questions you know and bookmark the ones you don't. Every exam lets you come back to bookmarked questions.

On your second pass, return to your bookmarks one at a time. You have 4 hours for 80 questions, which is about 3 minutes per question, so keep moving and don't let one question hold you up. Before you finish, answer anything you skipped. A blank can't earn a point.

Study Tips

On an open-book exam, the winners aren't the smartest people in the room — they're the fastest at finding answers. Buy the required book, practice with it open, and tab and highlight each section the first time a question sends you there. Learn the index and table of contents until you can land on any topic in seconds. That speed is what separates a pass from a fail.

On an open-book exam, work through every question once: answer the ones you know and skip the ones you don't. Then go back to the ones you flagged. You can bookmark questions for later review, just like on our exams — and don't sink too much time into any single question. The clock is still running.

Give yourself at least three to six weeks. Use your exam's candidate bulletin as your roadmap for what's tested, and spend your time on finding-it-fast skills over rote memorization. In practice, aim for three clean passes at 80% or higher — setting your practice bar above the real cut score gives you a comfortable margin on test day.

Practicing against a ticking clock is the best way to beat exam-clock anxiety. Use these timed tests to build your pacing, so you learn to move steadily and never burn too long on a single question. By test day, the format feels routine.

Sample Mississippi HVAC Practice Questions

Here are a few questions from our practice question bank, each with its answer and reference.

Sample 1 — Refrigerants and Refrigeration

Question: You are preparing to replace a failed compressor on a commercial refrigeration system and want to remove the suction service valve from the compressor while leaving the suction line sealed, so the entire system charge does not have to be recovered. Into which position must the suction service valve stem be placed?

A. Front seated
B. Back seated
C. Cracked open
D. Mid-position

Correct Answer: A

Per Section 11.3.2 (Low-Side Service Valves) of Modern Refrigeration and Air Conditioning, front seating a suction service valve blocks the suction line's passage into the valve while leaving a passage between the service port and the valve outlet to the compressor. This lets the technician remove the valve from the compressor with the suction line sealed. Back seating closes the service port for normal operation; mid-position and cracked open both leave refrigerant flowing through the valve.

Reference: Modern Refrigeration and Air Conditioning (22nd ed.), Page 198

Sample 2 — LP Gas Systems

Question: You are installing an appliance shutoff valve. What is the maximum distance the shutoff valve may be located from the appliance when installed in the same room?

A. 4 feet
B. 10 feet
C. 6 feet
D. 3 feet

Correct Answer: C

Per IFGC Section 409.5.1, the shutoff valve shall be located in the same room as the appliance. The shutoff valve shall be within 6 feet (1829 mm) of the appliance and shall be installed upstream of the union, connector, or quick disconnect device it serves.

Reference: IFGC 2021 Page 4-47

Sample 3 — Piping

Question: When troubleshooting a globe valve, you discover that the handwheel turns but the disc does not move. A bent or scored stem has been identified as the cause of stem leakage. What is the correct remedy for the bent or scored stem?

A. Tighten the packing gland nut
B. Replace the gasket and reseat the disc
C. Replace the packing material
D. Replace the stem

Correct Answer: D

When leakage around the stem of a globe valve is caused by a bent or scored stem, the recommended remedy is to replace the stem. Other causes of stem leakage include a loose packing gland or nut (tighten it) or worn-out packing (replace packing).

Reference: Pipefitter's Handbook (3rd ed.), Chapter 1 (Full Text), Trouble Shooting Methods — Globe Valves

Sample 4 — A/C and Heat Pump Equipment

Question: In a residential HVACR system, what is the primary purpose of a control transformer?

A. To provide backup power during a utility outage
B. To increase line voltage for the compressor motor
C. To convert three-phase power to single-phase power
D. To step down line voltage to a lower voltage for the control circuit

Correct Answer: D

A control transformer steps down the higher line voltage (typically 120 V or 240 V) to a lower voltage (typically 24 V) to power the control circuit, which includes thermostats, relays, and contactor coils. This lower voltage makes control circuits safer and simpler to operate.

Reference: Modern Refrigeration and Air Conditioning (22nd ed.), Chapter 23 - Residential Split Air-Conditioning Systems, Page 479 (Section 23.2.1) (20th ed.: Chapter 12, Section 12.7)

Practicing Online vs. With a PDF

A PDF lets you read questions at your own pace. The real exam runs on a clock. Our practice exams are timed and on a screen, so you practice finding answers with the clock running. Each attempt draws a new set of questions from our bank, and your results show your score by topic, so you always know what to study next.

Your Next Step

Take the free Mississippi HVAC practice exam to see where you stand. Then study the topics that need the most attention, one at a time. For the official rules, read the exam bulletin, and see the licensing board's website.

Frequently Asked Questions

How many questions are on the Mississippi HVAC contractor exam and how long do I have?

The Mississippi HVAC exam has 80 questions and you are given 4 hours to complete it.

What is the passing score for the Mississippi HVAC exam?

You must achieve a minimum score of 70% to pass the Mississippi HVAC exam.

How much does it cost to register for the Mississippi HVAC exam?

The registration fee is $120 for one examination portion. If you need to take two examination portions, the fee is $240. Fees are not refundable or transferable.

How do I register or schedule the Mississippi HVAC exam?

You can register online at PSI's registration website or by calling PSI at (855) 557-0619. Internet registration is available 24 hours a day, and phone registration is available Monday through Friday and on weekends during listed hours.

How do I become eligible to take the Mississippi HVAC exam?

You must first request an application package from the Mississippi Contractor Licensing Board and submit the appropriate application. The Board will determine your eligibility and notify PSI, who will then email you a confirmation notice.

How long do I have to pass the Mississippi HVAC exam after I am approved?

You have 6 months from the date of eligibility to pass the exam. During that 6-month period you may retest on an unlimited basis if you fail. If you do not pass within 6 months, you must reapply with the Board.

Is the Mississippi HVAC exam open book, and what references can I bring?

Yes, the HVAC exam is open book. Approved references include books such as Modern Refrigeration and Air Conditioning (22nd edition; the 20th and 21st editions are no longer used as of 8/1/2026), the International Fuel Gas Code (2021), the International Mechanical Code (2021), HVAC Duct Construction Standards, Manual J, Manual N, Manual D, NFPA 58, the ACCA Ductulator, and the Pipefitters Handbook. You must bring your own references; they may be highlighted, underlined, or indexed with permanent tabs, but may not be written in and cannot contain additional loose papers.

Can I bring a calculator to the Mississippi HVAC exam?

Yes, you may bring a silent, battery-operated, non-programmable calculator that has no paper tape printing capability and no alphabetic keyboard.

What identification do I need to bring on exam day?

You must bring one valid, non-expired government-issued photo ID that also bears your signature, such as a state driver's license, state ID card, U.S. passport, U.S. military ID, U.S. alien registration card, or Canadian government-issued ID. The name on your ID must exactly match the name under which you registered.

When will I get my score after taking the Mississippi HVAC exam, and what happens after I pass?

Your score is displayed on the computer screen immediately after you finish the exam. After passing and meeting all licensing requirements, the Board reviews applications weekly and successful candidates receive their Certificate of Responsibility approximately one week after Board approval.

Mississippi HVAC